on board battery advice please
 

Would welcome some advice on using lithium polymer batteries for on board systems to keep weight down. I realise the turbine pack is easily replaced, but am concerned about how I can use a battery backer system for the radio gear. I would normally use two 5 cell nicad packs and a backer system but want to save weight. Can anyone advise me how to use multiple lipos to have a redundancy on the radio gear.

Help and suggestions very welcome thanks.

Paul.